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The Wizarding World is a dangerous place — full of dark wizards, unforgivable curses, and untold evils (like earwax flavored jellybeans). But it turns out the prospect of making the films based on the bestselling book series could occasionally be quite dangerous as well.

Oliver Phelps, who portrayed George Weasley (one half of the Weasley twin duo Fred and George) across all eight films, explains that a stunt during Harry Potter and the Goblet of Fire turned out to be trickier than anticipated.

Phelps, alongside his brother James, trained to film the memorable scene in which Fred and George attempt to trick the Goblet of Fire into believing they’re above the requisite age limit and are thrown backwards from the cup with a pair of white beards and long hair. In addition to being fitted for hand-made wigs and beards totaling six pieces featuring delicate individually woven hairs, the twins prepared to be shot out of the Goblet’s space in the Great Hall.

“We did some training with the stunt guys on the harness being thrown up and landing on to the mats on the floor,” he explains. But when it came time to film the scene, the production team decided to leave the stunt to the professionals. “We were both a bit annoyed about that. We want to be able to say we did our stunts and stuff,” Phelps explains. “But it turned out the guy who played myself or James ended up dislocating his elbow on the fall, so it was probably a good job they knew what they were doing with that and didn’t let us do it because it was quite the dangerous stunt.”

The scene ends with a scuffle between Fred and George, which required the Phelps twins to roll around on the floor of the Great Hall. Getting it right meant director Mike Newell also had to roll up his sleeves and join in the fight. “We didn’t really know what to do, so we did one thing and Mike just said, ‘No, no, no who wants to fight me?’” Phelps explains. “I looked up and said, ‘Ok, I will.’ Mike literally jumped on top of me and is going, ‘Throw me off, throw me off!’ I almost threw him over and he was like, ‘Right, do that.’”

That bit of fisticuffs might not have been dangerous for Oliver and James, but it still was a horror show for the hair and make-up team. “We could just look over and see Amanda from hair and make-up, whose in charge of these wigs and amazingly expensive beards, in sheer horror at us throwing ourselves around,” he recalls.

The make-up team got the last laugh though. Phelps’ brother, James, had a fresh shave the morning they filmed the scene, making his skin particularly vulnerable to the glue used to attach the intricate wig and beard. “When they took it off with the methanol, you could hear him from down the hall,” recalls Phelps with a laugh.